Nope, nope & nope, & their are white Pelt slags, there are pictures in Sami's book of full boxes of them both feathered and not feathered. pg. 213 shows a single row in a pelt box, pg. 179 shows a 100 count box full of white Peltier feather slags (every one) owned by Marty Ruhland, indeed VVVHTF
LINK :: https://www.allaboutmarbles.com/viewtopic.php?f=5&t=51150&p=368876&hilit=White+Peltier+Slags#p368876
There's a picture of Ron's White pelt slag on this link
LINK :: https://www.allaboutmarbles.com/viewtopic.php?f=5&t=5920&p=45748&hilit=White+Peltier+Slags#p45748